Rack level pre-installed interconnect for enabling cableless server/storage/networking deployment

ABSTRACT

Apparatus and methods for rack level pre-installed interconnect for enabling cableless server, storage, and networking deployment. Plastic cable waveguides are configured to couple millimeter-wave radio frequency (RF) signals between two or more Extremely High Frequency (EHF) transceiver chips, thus supporting millimeter-wave wireless communication links enabling components in the separate chassis to communicate without requiring wire or optical cables between the chassis. Various configurations are disclosed, including multiple configurations for server chassis, storage chassis and arrays, and network/switch chassis. A plurality of plastic cable waveguide may be coupled to applicable support/mounting members, which in turn are mounted to a rack and/or top-of-rack switches. This enables the plastic cable waveguides to be pre-installed at the rack level, and further enables racks to be installed and replaced without requiring further cabling for the supported communication links. The communication links support link bandwidths of up to 6 gigabits per second, and may be aggregated to facilitate multi-lane links.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/331,250, filed on Oct. 21, 2016, which is a Continuation ofU.S. patent application Ser. No. 14/227,497, filed on Mar. 27, 2014, nowU.S. Pat. No. 9,496,592, issued on Nov. 15, 2016, which is herebyincorporated herein by reference in its entirety and for all purposes.

BACKGROUND INFORMATION

Ever since the introduction of the microprocessor, computer systems havebeen getting faster and faster. In approximate accordance with Moore'slaw (based on Intel® Corporation co-founder Gordon Moore's 1965publication predicting the number of transistors on integrated circuitsto double every two years), the speed increase has shot upward at afairly even rate for nearly three decades. At the same time, the size ofboth memory and non-volatile storage has also steadily increased, suchthat many of today's personal computers are more powerful thansupercomputers from just 10-15 years ago. In addition, the speed ofnetwork communications has likewise seen astronomical increases.

Increases in processor speeds, memory, storage, and network bandwidthtechnologies have resulted in the build-out and deployment of networkswith ever increasing capacities. More recently, the introduction ofcloud-based services, such as those provided by Amazon (e.g., AmazonElastic Compute Cloud (EC2) and Simple Storage Service (S3)) andMicrosoft (e.g., Azure and Office 365) has resulted in additionalnetwork build-out for public network infrastructure, in addition to thedeployment of massive data centers to support these services that employprivate network infrastructure.

Cloud-based services are typically facilitated by a large number ofinterconnected high-speed servers, with host facilities commonlyreferred to as server “farms” or data centers. These server farms anddata centers typically comprise a large-to-massive array of rack and/orblade servers housed in specially-designed facilities. Many of thelarger cloud-based services are hosted via multiple data centers thatare distributed across a geographical area, or even globally. Forexample, Microsoft Azure has multiple very large data centers in each ofthe United States, Europe, and Asia. Amazon employs co-located andseparate data centers for hosting its EC2 and AWS services, includingover a dozen AWS data centers in the US alone.

In order for the various server blades and modules to communicate withone another and to data storage, an extensive amount of cabling is used.Installing the cabling is very time-consuming and prone to error. Inaddition, the cost of the cables and connectors themselves aresignificant. For example, a 3-foot SAS (Serial attached SCSI) cable maycost $45 alone. Multiply this by thousands of cables and installations,and the costs add up quickly, as does the likelihood of cabling errors.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated as the same becomesbetter understood by reference to the following detailed description,when taken in conjunction with the accompanying drawings, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified:

FIG. 1 illustrates a radio frequency antenna output emitted from atransmitter EHF transceiver chip and being received by a receiver EHFtransceiver chip;

FIG. 2 is a block diagram of one embodiment of an EHF transceiver chip;

FIGS. 3a-3d illustrate launch orientations between pairs of EHFtransceiver chips, wherein FIG. 3a depicts a vertical launch, FIG. 3bdepicts an offset vertical launch, FIG. 3c depicts a side launch, andFIG. 3d depicts a diagonal launch;

FIGS. 3e-3i, 3i-a and 3i-b illustrate various communication linkconfigurations between EHF transceiver chips having their signalscoupled via plastic cable waveguides, wherein FIG. 3e depicts two EHFtransceiver chips in the same orientation, FIGS. 3f-3h depict pairs ofEHF transceiver chips oriented 90° apart, and FIGS. 3i, 3i-a, and 3i-bdepict three EHF transceiver chips in the same orientation, wherein FIG.3i depicts no sheet between the ends of the plastic cable waveguide andthe EHF transceiver chips, FIG. 3i-a includes a sheet with holes throughwhich the signals are passed, and FIG. 3i-b shows the legs of theplastic cable waveguide passing through holes in a sheet;

FIGS. 4a and 4b illustrate a millimeter-wave wireless link betweenrespective EHF transceiver chips in a blade server chassis above astorage array chassis under which signals are passed through holes inthree metal layers, according to one embodiment;

FIG. 4c illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a blade server chassis above a storage arraychassis under which signals are passed through holes in one plasticlayer and two metal layers, according to one embodiment;

FIG. 4d illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a storage array chassis above a blade serverchassis under which signals are passed through holes in three metallayers, according to one embodiment;

FIG. 4e illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a storage array chassis above a blade serverchassis under which signals are passed through holes in two metallayers, according to one embodiment;

FIG. 4f illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a storage array chassis above a blade serverchassis under which signals are passed through a hole in one metallayer, according to one embodiment;

FIGS. 5a and 5b illustrate a millimeter-wave wireless link betweenrespective EHF transceiver chips in a network/switch chassis above ablade server chassis under which signals are passed through holes inthree metal layers, according to one embodiment;

FIG. 5c illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis under which signals are passed through one plastic layer andholes in two metal layers, according to one embodiment;

FIG. 5d illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis under which signals are passed through holes in two metallayers, according to one embodiment;

FIG. 5e illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis with an open top under which signals are passed through holes intwo metal layers, according to one embodiment;

FIG. 5f illustrates a millimeter-wave wireless link between respectiveEHF transceiver chips in a network/switch chassis above a blade serverchassis under which signals are passed through a hole in one metallayer, according to one embodiment;

FIG. 6 is a graphic diagram depicting an electromagnetic field strengthof signals emitted from a transmitting EHF transceiver chip and passingthrough holes in two metal layers using a vertical launch configuration;

FIG. 7 is a graphic diagram depicting an electromagnetic field strengthof signals emitted from a transmitting EHF transceiver chip and passingthrough holes in three metal layers using a diagonal launchconfiguration;

FIGS. 8a and 8b illustrate a configuration under which an array of EHFtransceiver chips in a server chassis are wirelessly linked with anarray of EHF transceiver chips in a storage chassis below the serverchassis, according to one embodiment;

FIGS. 9a and 9b illustrated a modified version of the configuration ofFIGS. 8a and 9b further adding four fabric backplanes with EHFtransceiver chips on both sides in the server chassis, according to oneembodiment;

FIGS. 10a and 10b illustrate a configuration under which components in amiddle server chassis are enabled to wirelessly communicate withcomponents in storage chassis above and below the server chassis,according to one embodiment;

FIGS. 11a and 11b illustrate a configuration under which a 6U serverchassis is disposed below a network/switch chassis and above a storagearray, according to one embodiment;

FIGS. 12a and 12b respective show topside and underside isometricperspective views of a storage array employing an upper backplaneincluding an array of EHF transceiver chips, according to oneembodiment;

FIG. 12c shows a topside isometric perspective view of a storage arrayemploying EHF transceiver chips mounted to vertical boards to whichstorage drives are coupled, according to one embodiment;

FIG. 12d illustrates a backplane configured for use in a storage arrayincluding an array of SATA connectors on its topside and an array of EHFtransceiver chips on its underside;

FIGS. 13a and 13b illustrate a backplane configured for use in anetwork/switch chassis, according to one embodiment;

FIG. 14a shows a network switch chassis implementing the backplane ofFIGS. 13a and 13 b;

FIG. 14b shows a network switch chassis implementing two backplanes ofFIGS. 13a and 13b under which the upper backplane is inverted;

FIG. 15 illustrates a server module including a pair of EHF transceiverchips mounted to its main PCB board, according to one embodiment;

FIG. 16 is a schematic diagram illustrating a technique for combiningmultiple millimeter-wave wireless links in parallel to increase linkbandwidth, according to one embodiment;

FIG. 17a shows a server rack employing a rack level pre-installedinterconnect employing a plurality of plastic cable waveguides that areoperatively coupled to the rack and/or server and switch chassis andconfigured to coupled millimeter-wave RF signals between EHF transceiverchips in separate chassis;

FIG. 17b shows further details of the rack level pre-installedinterconnect structure, according to one embodiment;

FIG. 17c shows a frontal perspective view of the rack with multipleserver chassis removed to illustrate details of the provisions in theserver chassis for facilitating signal coupling between EHF transceiverchips inside of the chassis and plastic cable waveguides on the outsideof the chassis;

FIG. 17d shows an isometric perspective view of a server chassisconfigured to facilitate signal coupling between EHF transceiver chipsinside of the chassis and plastic cable waveguides on the outside of thechassis;

FIG. 17e shows four racks of servers with top of rack switches that arecommunicatively coupled through use of EHF transceiver chips andpre-installed interconnects comprising plastic cable waveguides;

FIG. 17f shows a frontal perspective view illustrating the routing ofplastic cable waveguides in a manner that facilitates coupling ofmillimeter-wave RF signals between servers in one rack and top of therack switches in the adjacent rack;

FIGS. 18a and 18b show further details of a top-of-rack switch andpre-installed interconnect configuration illustrated in FIGS. 17a-17c,17e, and 17f , according to one embodiment;

FIGS. 19a and 19b shows another embodiment of a rack of serversemploying a pre-installed interconnect comprising a plurality of plasticcable waveguide configured to couple millimeter-wave RF signals betweenEHF transceiver chips in different chassis;

FIG. 19c shows an isometric frontal view of a server chassis configuredto be used in the server rack of FIG. 19a , according to one embodiment;and

FIGS. 19d and 19e illustrate the location of EHF transceiver chipsrelative to dielectric manifolds used for couple millimeter-wave RFsignals into and out of the plastic cable waveguides.

DETAILED DESCRIPTION

Embodiments of apparatus and methods for rack level pre-installedinterconnect for enabling cableless server, storage, and networkingdeployment are described herein. In the following description, numerousspecific details are set forth to provide a thorough understanding ofembodiments described and illustrated herein. One skilled in therelevant art will recognize, however, that the invention can bepracticed without one or more of the specific details, or with othermethods, components, materials, etc. In other instances, well-knownstructures, materials, or operations are not shown or described indetail to avoid obscuring aspects of the invention.

For clarity, individual components in the Figures herein may also bereferred to by their labels in the Figures, rather than by a particularreference number. Additionally, reference numbers referring to aparticular type of component (as opposed to a particular component) maybe shown with a reference number followed by “(typ)” meaning “typical.”It will be understood that the configuration of these components will betypical of similar components that may exist but are not shown in thedrawing Figures for simplicity and clarity or otherwise similarcomponents that are not labeled with separate reference numbers.Conversely, “(typ)” is not to be construed as meaning the component,element, etc. is typically used for its disclosed function, implement,purpose, etc.

In accordance with aspects of the embodiments disclosed herein,Extremely High Frequency (EHF) wireless communication links are used inplace of conventional cabling techniques, resulting in reductions inboth system component costs and labor costs. The Extremely HighFrequency range is approximately 10 GHz-300 GHz. The embodimentsleverage recent advancements in very short length millimeter-wavewireless transceiver chips to facilitate contactless communication linksfor blade server and other high-density module configurations applicablefor data centers and the like. As used herein, the terminology“millimeter-wave” means the wavelength of the radio frequency signals ison the order of a millimeter, which may include RF signals withsub-millimeter length within the EHF range. Additionally, theembodiments facilitate use of existing and future server blade andserver module configurations.

FIG. 1 illustrates radio frequency (RF) signal energy being output by anantenna in a first EHF transceiver chip 100 operating as a transmitter(Tx or TX) and being received by a second EHF transceiver chip 102 thatis operating as a receiver (Rx or RX). As illustrated by the darkershading representing higher energy density, the electromagnetic fieldstrength of the RF signal dissipates with distance from the transmitter.

In one embodiment, each of EHF chips 100 and 102 comprise EHF chipsmanufactures by WaveConnex, Inc., Mountainview, Calif. In oneembodiment, the EHF chips illustrated in the Figures herein comprise aWaveConnex WCX102 (or WCX102b) transceiver chip. Details of thestructure and operations of the millimeter-wave technology implementedin the WaveConnex chips are disclosed in U.S. Pat. No. 8,554,136entitled “TIGHTLY-COUPLED NEAR-FIELD COMMUNICATION-LINKCONNECTOR-REPLACEMENT CHIPS,” and U.S. application Ser. No. 13/471,052(U.S. Pub. No. 2012/0286049 A1) and Ser. No. 13/471,058 (U.S. Pub. No.2012/0290760 A1), both entitled “SCALABLE HIGH-BANDWIDTH CONNECTIVITY.”

FIG. 2 shows a block diagram 200 of an embodiment of an EHF transceiverchip. The basic chip blocks includes a Tx baseband block 202, RF blocks204, and an Rx baseband block 206. The RF blocks include an EHFtransmitter block 208, an EHF receiver block 210, and an antenna 212.The EHF chip is configured to receive a stream of data to be transmittedfrom an external component using a differential signal at pins TXinP(positive) and TXinN (negative). The input transmitted digital stream isprocessed by Tx baseband block 202 and EHF transmitter block 208 tocreate a modulated RF signal that is radiated output from antenna 212.Antenna 212 also receives signals transmitted from a paired EHFtransceiver of similar configuration (not) shown, with the receivedsignals processed by EHF receiver block 210 and Rx baseband block 206 togenerate a received bitstream encoded using differential signaling thatis output at the RXoutP and RXoutN pins. In one embodiment, the EHFtransceiver chip employs a 60 GHz carrier that is generated on-chip,with the modulated signal sent to antenna 212 for transmission.

The EHF transceiver chip includes multiple control inputs 214 that areused for various control and configuration purposes. The control inputsenable the transceiver chip to be configured in two operating modes,including a high-speed mode, intended for use with DC balanceddifferential signals that is suitable for signals running from 100 Mb/sto 6.0 Gb/s and features support for envelope-based Out-of-Band (OOB)signaling used in Serial-Attached-SCSI (SAS) and Serial AdvancedTechnology Attachment (SATA), as well as electrical idle and LowFrequency Periodic Signaling (LFPS) signals in Peripheral ComponentInterconnect Express (PCIe) and Universal Serial Bus version 3.0 (USB3.0).

The EHF transceiver chips are configured to facilitate very short rangewireless communication links between pairs of transceiver chips invarious orientations. For example, a pair of chips may be configuredwith the top surfaces opposite one another as shown by the verticallaunch configuration of FIG. 3a . As shown in FIG. 3b , the antennas ofa pair of EHF transceiver chips do not need to be in alignment. FIG. 3cshows a configuration under which a pair of EHF transceiver chips 100and 102 are in substantially the same plane. In addition to thisconfiguration, a pair of EHF transceiver chips can be in respectiveparallel planes that are closely spaced (e.g., within a 5-15millimeters). As shown in FIG. 3d , a diagonal launch configuration isalso supported.

In accordance with further aspects of some embodiments, EHF transceiverchips are configured to support a plurality of very short lengthmillimeter-wave wireless links between circuitry and components inphysically separate enclosures, such as chassis employed in standard 19″racks. By way of example and without limitation, a configuration 400 isshown in FIGS. 4a and 4b under which circuitry on a server blade 402 ina blade server chassis 404 is linked in communication with a disk drive406 in a storage array chassis 408. In further detail, server blade 402includes a main board 410 to which an EHF transceiver chip 412 ismounted. As an option, an EHF transceiver chip may be mounted to adaughter board or otherwise comprise part of a multi-board module. Inthe illustrated embodiment of FIG. 4a , server blade 402 is eithermounted within an enclosure including a cover plate 414 or is coupled tothe cover plate 414 in which a hole 416 is formed. Similarly-sized holes418 and 420 are respectively formed in the sheet metal baseplate 422 ofblade server chassis 404 an in a top plate 424 of storage array 408.Preferably, holes 416, 418, and 420 are substantially aligned to form anopen pathway 426 through cover plate 414, baseplate 422 and top plate424, enabling transmission of RF energy between EHF transceiver chip 412and an EHF transceiver 428 mounted to a backplane 430 in storage arraychassis 408. Baseplate 430 includes a plurality of Serial ATA (SATA)connectors 432 to which disk drive 406 is connected.

In one embodiment, EHF transceiver chip 428 is configured to performsignaling to support a SATA interface to facilitate communicationbetween disk drive 406 and the EHF transceiver chip using the SATAprotocol. Accordingly, configuration 400 enables circuitry on serverblade 410 to write data to and read data from a disk drive 406 in aseparate chassis via an EHF millimeter-wave bi-directional wireless link434. As a result, configuration 400 removes the need for use of physicalcabling between blade server chassis 404 and storage array chassis 408.

Exemplary variations of configuration 400 are shown in FIGS. 4c, 4d, 4e,and 4f . Under a configuration 400 c of FIG. 4c , a server blade 402 ais mounted within an enclosure including a plastic cover plate 415 orotherwise cover plate 415 is attached to main board 410. Unlike metals,which generally attenuate RF signals in the EHF frequency range, variousplastics may be employed that provide substantially insignificantattenuation. Accordingly, there is no hole formed in cover plate 415 inthe illustrated embodiment. Alternatively, a hole could be formed incover plate 415 depending on the attenuation of the cover plate materialin the EHF frequency range.

Under configurations 400 d, 400 e and 400 f of respective FIGS. 4d, 4e,and 4f , the storage array chassis 408 is placed above blade serverchassis 404, and the rest of the components are generally flippedvertically. Configuration 400 d is similar to configuration 400, andincludes the passing of EHF millimeter-wave bi-directional wireless link434 via an open pathway formed by holes 416, 418, and 420 through coverplate 414, baseplate 422 and top plate 424.

Under some blade server chassis configuration, blade servers or servermodules are inserted vertically and may be “hot-swapped” without havingto power down the entire chassis. In addition, there are similar bladeserver chassis configurations under which the chassis does not include atop or cover plate, since this would need to be removed to remove orinstall server blades or modules. Such a configuration 400 e is shown inFIG. 4e , wherein blade server chassis 404 a does not include a coverplate. In this instance, RF signals to facilitate EHF millimeter-wavebi-directional wireless link 434 only need to pass through two metalsheets corresponding to base plate 424 of storage array chassis 408 anda cover plate 423 of a server blade 402 b. The also reduces the distancebetween EHF transceiver chips 412 and 428.

Under configuration 400 f shown in FIG. 4f , the RF signals only need topass through a single metal sheet corresponding to the base plate 424 ofstorage array chassis 408. In this configuration, a blade server 402 cdoes not include a cover plate. Optionally, the server blade or modulecould include a plastic cover plate (not shown) through which a hole mayor may not be formed. As with blade server chassis 404 a in FIG. 4e ,blade server chassis 404 b does not include a cover plate.

FIGS. 5a-5f illustrate various configurations under which server bladesin a blade server chassis are enabled to wirelessly communicate withnetworking and/or switching components in a separate chassis. Forexample, FIGS. 5a and 5b illustrate a configuration 500 under which aserver blade 502 in a blade server chassis 504 is enabled to communicatewith networking circuitry on a backplane 506 in a network/switch chassis508 via a an EHF millimeter-wave bi-directional wireless link 510facilitated by a pair of EHF transceiver chips 512 and 514. As before,EHF transceiver chip 512 is mounted to a main board 516 (ordaughterboard or similar) of server blade 502, which includes either anenclosure having a cover plate 518 or cover plate 518 is coupled to mainboard 516. The other two sheet metal layers illustrated in FIGS. 5a and5b correspond to a blade server chassis cover plate 520 and a bottomplate 522 of network/switch chassis 508. Respective holes 524, 526, and528 are formed in cover plate 518, cover plate 520, and bottom plate522, thereby creating an open pathway 530 through which EHFmillimeter-wave bi-directional wireless link 510 RF signals propagate.

Configuration 500 c of FIG. 5c illustrates a server blade or module 502a that employs a plastic cover plate 519 rather than a metal coverplate. As above, depending on the attenuation of EHF RF signals by theplastic material, a hole through the cover plate may or may not need tobe formed. Under a configuration 500 d of FIG. 5d , server blade ormodule 502 b does not employ a cover plate. Under a configuration 500 eshown in FIG. 5e , blade server chassis 504 a does not employ a coverplate, while server blade or module 502 c employs a metal cover plate521 with a hole 527 formed through it. Optionally, cover plate 521 couldbe made of plastic and may or may not include a hole (not shown). Undera configuration 500 f of FIG. 5f , neither blade server chassis 504 anor server blade/module 502 d employ a cover plate. Thus, the RF signalsfor EHF millimeter-wave bi-directional wireless link 510 only need topass through a single metal sheet corresponding to bottom plate 522 ofnetwork/switch chassis 508.

As with any RF signal, the strength of the EHF millimeter-wave signal isa function of the RF energy emitted for the RF source (e.g., antenna)and the spectral attributes of the signal. In turn, the length of thewireless link facilitated between a pair of EHF transceiver chips willdepend on the amount of RF energy received at the receiver's antenna andsignal filtering and processing capabilities of the EHF receivercircuitry. In one embodiment, the aforementioned WCX100 chip supportsmultiple power output levels via corresponding control inputs via one ormore of control pins 214. Under one embodiment, the distance between EHFtransceiver chips is 2-15 mm, noting that this is merely exemplary andnon-limiting. Generally, higher data transmission link bandwidth may beachieved when the link's pair of EHF transceiver chips are closertogether and/or using more power.

To verify link performance capabilities and expectations under some ofthe embodiments disclosed herein, computer-based RF modeling wasperformed. Under one approach, the computational software (ANSYS HFSS)generated a visual representation of the signal strength of the RFsignals emitted from a transmitting EHF transceiver chip. The modelsalso considered the effect of the metal sheets/plates between pairs ofEHF transceiver chips under various configurations.

A snapshot 600 of the RF energy pattern for a configuration under whichthe RF signal emitted from a transmitting EHF transceiver chip 602 ismodeled as passing through two metal sheets 604 and 606 before beingreceived by a receiving EHF transceiver chip 608 is shown in FIG. 6. Themodel graphically illustrates the electro-magnetic field energy level indecibels. FIG. 7 shows a snapshot 700 of the RF energy pattern for aconfiguration under which the RF signal emitted from a transmitting EHFtransceiver chip 702 is modeled as passing through three metal sheets704, 706 and 708 before being received by a receiving EHF transceiverchip 710. In addition to these configurations, various otherconfigurations were modeled, including variations in the size of theholes in the metal sheets/plates, the number of metal sheets/plates, thedistance between the pair of EHF transceiver chips, the orientation ofthe EHF transceiver chips (e.g., vertical launch, side launch, diagonallaunch, amount of alignment offset, etc.).

Generally, the teachings and principles disclosed herein may beimplemented to support wireless communication between components inseparate chassis that are adjacent to one another (e.g., one chassis ontop of another chassis in the rack). Various non-limiting examples ofconfigurations supporting wireless communication between chassis usingEHF transceiver chips are shown in FIGS. 8a, 8b, 9a, 9b, 10a, 10b, 11a,11b, 12a, 12b, 13a , 13 b, 14 a, and 14 b. It will be understood thatthe configurations shown in these figures are simplified to emphasizethe millimeter-wave wireless communication facilitated through use ofEHF transceiver chips. Accordingly, these illustrative embodiments mayshow more or less EHF transceiver chips than might be implemented, andactual implementations would include well-known components that are notshown for convenience and simplicity in order to not obscure theinventive aspects depicted in the corresponding Figures. In addition,the illustrated embodiment may not be to scale, and may present partialor transparent components to reveal other components that wouldotherwise be obscured.

In a configuration 800 of FIGS. 8a and 8b , an array of server modules802 are mounted to backplanes 804, 806, 808, and 810 in an upper serverchassis 812. In one exemplary embodiment, server modules 802 comprisingIntel® Avoton™ servers modules. Meanwhile, a plurality of storage drives814 are coupled to backplanes 816, 818, 820, and 822 in a lower storagechassis 824. Each of backplanes 804, 806, 808, and 810 contain an arrayof downward-facing EHF transceiver chips 826, while each of backplanes816, 818, 820, and 822 contain an array of upward-facing EHF transceiverchips 828, wherein the arrays of the EHF transceiver chips areconfigured such that the downward-facing EHF transceiver chips arealigned respective upward-facing EHF transceiver chips on a pairwisebasis. In addition to what is shown in FIGS. 8a and 8b , there would bearrays of holes (not shown) in a bottom 830 of upper chassis 812 and acover plate (not shown) of lower storage chassis 824.

FIGS. 9a and 9b show a configuration 1000 under which a server chassis812 a comprising a modified version of server 812 is installed above astorage chassis 824. As illustrated, server chassis 812 now furtherincludes four fabric backplanes 904, 906, 908 and 910 disposed belowbackplanes 804, 806, 808, and 810. Each of fabric backplanes 904, 906,908 and 910 includes an array of upward-facing EHF transceiver chips 912mounted to its topside an array of downward-facing EHF transceiver chips914 mounted to its underside. Upward-facing EHF transceiver chips 828are configured to be substantially aligned with downward-facingtransceiver chips 826 on backplanes 804, 806, 808, and 810. Similarly,downward-facing EHF transceiver chips 914 are configured to besubstantially aligned with upward-facing transceiver chips on 828 onbackplanes 816, 818, 820, and 822.

FIG. 10a shows a configuration 1000 under which a middle server chassis1002 is sandwiched between an upper storage chassis 1004 and a lowerstorage chassis 1006, with further details of middle server chassis 1002depicted in FIG. 10b . Server chassis 1002 includes server boardassemblies 1026, each including a backplane 1010 to which variouscomponents are mounted on a topside thereof including a processor 1012,a plurality of memory modules 1014, and an InfiniBand host bus adaptor(HBA) 1016. Processor 1012 is generally illustrative of one or moreprocessors that may be included with each server board assembly 1008. Anarray of EHF transceiver chips 1020 are mounted to the underside of eachbackplane 1010. In addition, there would be a hole pattern having aconfiguration similar to the EHF transceiver chips 1020 in the baseplate 1022 of a chassis frame 1024 (not shown for clarity).

As shown in FIG. 10a , server chassis 1002 also includes an upper set offour backplanes 1026, each including an array of upward-facing EHFtransceiver chips 1028. In one embodiment, backplanes 1026 arecommunicatively coupled to backplanes 1010 via some form of physicalconnections, such as but not limited to connectors between pairs ofbackplanes or ribbon cables. In the illustrated embodiments, pairs ofupper and lower backplanes are each connected to an HBA 1016 thatfurther supports communication between the backplanes.

Lower storage chassis 1006 is generally configured in a similar mannerto lower storage chassis 824, except the shape of each of fourbackplanes 1030 is different than backplanes 816, 818, 820, and 822. Asbefore, an array of upward-facing EHF transceiver chips 1032 is mountedto each backplane 1030, while a plurality of storage drives 1034 arecoupled to an underneath side of the backplanes via applicableconnectors. There also would be an array of holes in the cover plate oflower storage chassis 1006 (not shown) that would be aligned with thearray of EHF transceiver chips 1032.

Upper storage chassis 1004 is generally configured in a similar mannerto lower storage chassis 1006, but with its vertical orientationflipped. As a result, each of four backplanes 1036 include a pluralityof storage devices 1038 coupled to its topside, and an array ofdownward-facing EHF transceiver chips 1040. Upper storage chassis 1004would also have an array of storage drives 1038.

FIGS. 11a and 11b illustrate a configuration 1100 including a 6U bladeserver chassis 1102 disposed under a switch chassis 1104 and above astorage array 1006. As shown in FIG. 11b , arrays of holes are formed ina cover plate 1108 of storage array 1006 and in a base plate 1110 ofswitch chassis 1004. Each of a plurality of server blades 1112 installedin blade server chassis 1102 includes a frame having an upper plate 1114and a lower plate 1116 through which a plurality of holes are formedadjacent to EHF transceiver chips along the top and bottom edges of theserver blade's main board (not shown), which is mounted to the frame. Inaddition, the cover and base plate of blade server chassis 1102 (notshown) will also include a plurality of holes that are substantiallyaligned with the holes in upper plate 1114 and lower plate 1116 whenblade servers 1112 are installed in server chassis 1002.

FIGS. 12a and 12b show further details of storage array 1106, accordingto one embodiment. A plurality of storage drives 1200 are mounted to andcommunicatively coupled with (e.g., via SATA connectors) vertical boards1202. In turn, the vertical boards 1202 are communicatively coupled witha backplane 1204 including an array of EHF transceiver chip 1206. In theillustrated embodiment, storage drives comprise 2½ inch drives that aremounted back to back. Storage drives having other form factors, such as3½ inch drives may be used in other embodiments.

FIG. 12c shows an embodiment of a storage array 1106 a. Under theillustrated configuration, EHF transceiver chips 1208 are mounted towardthe top of vertical boards 1202. In the illustrated embodiment one EHFtransceiver chip 1208 is implemented for each drive; however, this ismerely exemplary, as multiple EHF transceiver chips may be used for oneor more drive. Also in the illustrated embodiment the EHF transceiverchips 1208 are mounted on a single side of vertical boards 1202;optionally, EHF transceiver chips may be mounted on both sides of thevertical boards.

As shown in FIG. 12d , in one embodiment a plurality of SATA connectors1210 are mounted to a backplane 1212 having an array of EHF transceiverchips 1214. In one configuration, backplane 1212 is disposed in thebottom of a chassis with SATA connectors 1210 pointing upward and EHFtransceiver chips 1214 pointing downward. In another configuration,backplane 1212 is inverted and disposed toward the top of a chassis withEHF transceiver chips 1214 pointing upward and SATA connectors 1210pointing downward.

EHF transceiver chips may be implemented in networking related chassis,such as switch chassis and network chassis or a network/switch chassisthat includes components supporting networking and switching functions.Generally, a network/switch chassis may employ a single backplane or twobackplanes arrayed with EHF transceiver chips, such as illustrated by anetwork/switch backplane 1300 in FIGS. 13a and 13b . In this example, aplurality of Ethernet network connectors 1302 comprising RJ45 Ethernetjacks are mounted on a topside of network/switch backplane 1300, whilean array of EHF transceiver chips 1304 are mounted on the underside ofthe backplane. Wire traces in network/switch backplane 1300 are routedto network connectors 1302 and a multi-port network/switch chip 1304.Although only a single multi-port network/switch chip is shown, it willbe understood that multiple chips of similar configuration may beimplemented on a network/switch backplane, and that network ports andswitch operations may also be implemented on separate chips or otherwiseusing separate circuitry and logic. Multi-port network/switch chip 1304also is connected via wire traces in network/switch backplane 1300 toEHF transceiver chips 1306. In addition, applicable interface circuitryand signal-conditioning circuitry (not shown) may be implemented usingtechniques and principles well-known in the art.

The terminology network/switch is meant to convey the apparatus may beimplemented for networking and switching functions. Depending on theparticular system needs or architecture, a network/switch chassis mayinclude various numbers of external network ports that are used tointerface with other servers, storage devices, etc. in other chassisand/or other racks, such as 4, 8 12, 16, 24, etc. In someimplementations, a network/switch backplane may be configured to supportswitching functionality related to internal communications in a mannersimilar to some switch cards used in data centers and the like.

FIGS. 14a and 14b respectively show exemplary 1U network/switch chassisthat support wireless connections with a chassis below (fornetwork/switch chassis 1400 a) and with both a chassis above and below(for a network/switch chassis 1400 b). As shown in FIG. 14a , anetwork/switch backplane 1300 is mounted within a 1U chassis frame 1402,with network connectors 1302 mounted toward the rear of the chassisframe.

Network/switch chassis 1400 b further adds a second network/switchbackplane 1300 a this is mounted such that EHF transceiver chips 1404are just below a top) of 1U chassis frame 1402 in which a plurality ofholes 1308 are defined proximate to each EHF transceiver chip.

A server module 1500 configured to facilitate wireless communicationwith components in another chassis is shown in FIG. 15. Server module1500 includes four CPU subsystems comprising Systems on a Chip (SoCs)1502 a, 1502 b, 1502 c, and 1502 d, each coupled to respective memories1504 a, 1504 b, 1504 c, and 1504 d. Each of SoCs 1502 a, 1502 b, 1502 c,and 1502 d is also communicatively coupled to PCIe interface 1506 via arespective PCIe link. Each of SoCs 1502 a, 1502 b, 1502 c, and 1502 dalso has access to an instruction storage device that containsinstructions used to execute on the processing cores of the SoC.Generally, these instructions may include both firmware and softwareinstructions, and may be stored in either single devices for a module,or each SoC may have its own local firmware storage device and/or localsoftware storage device. As another option, software instructions may bestored on one or more mass storage modules and accessed via an internalnetwork during module initialization and/or ongoing operations.

Each of the illustrated components are mounted either directly or via anapplicable socket or connector to a printed circuit board (PCB) 1510including wiring (e.g., layout traces and vias) facilitating transfer ofsignals between the components. This wiring includes signal paths forfacilitating communication over each of the PCIe links depicted in FIG.15. PCB 1510 also includes wiring for connecting selected components tocorresponding pin traces on an edge connector 1512. In one embodiment,edge connector 1512 comprises a PCIe edge connector, although this ismerely illustrative of one type of edge connector configuration and isnot to be limiting. In addition to an edge connector, an arrayed pinconnector may be used, and the orientation of the connector on thebottom of PCB 1510 in FIG. 15 is exemplary, as an edge or arrayed pinconnector may be located at an end of the PCB, which is a commonconfiguration for a blade server.

As further shown in FIG. 15, server module 1500 includes a pair of EHFtransceiver chips 1508 that are mounted toward the top edge of PCB 1510.This configuration is similar to that shown by Server Blade/Module 402in FIG. 4d , Server Blade/Module 402 b in FIG. 4e , and ServerBlade/Module 402 c in FIG. 4f . In general, a server module thatsupports communication via millimeter-wave wireless links may employ oneor more EHF transceiver chips, which may be mounted on one or both sidesof the modules main board and/or a daughterboard or the like.

FIG. 16 illustrates an example of combining multiple individualmillimeter-wave EHF links in parallel to support increased transferrates across communication interfaces. In the illustrated embodiment, aserver module 1500 a includes a four lane (4×) PCIe interface 1506, andis coupled to a PCIe connector 1600 supporting four (or more) PCIelanes. Pins corresponding to respective PCIe differential signal pairsare coupled to the differential TX input pins on each of a first set ofEHF transceiver chips 1602, which are wirelessly linked in communicationwith EHF transceiver chips 1604 on a pairwise basis. In turn, thedifferential RX output pins on EHF transceiver chips 1604 are coupled todifferential signal pair I/O pins on a PCIe interface chip 1606. Ingeneral, the technique illustrated in FIG. 16 may be used to support annx PCIe link wherein n is an integer number of lanes greater than one.For example, standard PCIe multi-lane links may be implemented, such as2×, 4×, 8×, 16×, etc. PCIe links.

Rack Level Pre-Installed Interconnect for Enabling CablelessServer/Storage/Networking Deployment

According to further aspects of the disclosure, EHF transceiver chipsmay be combined with pre-configured and/or installed waveguides made ofplastic or similar material to facilitate implementation of rack levelpre-installed interconnects that replace conventional cabling. Thisprovides both a cost savings from both a materials and laborconsideration. It further reduces or eliminates cabling errors, andfacilitates tighter rack spacing.

During experimentation with the EHF transceiver chips, the inventorsdiscovered that the millimeter-wave RF signals transmitted from a chipcould be coupled to one end of a plastic tie-wrap and transmitted outthe other end if the ends were cut-off cleanly. Moreover, the plastictie-wraps could be bent with minimal attenuation of the RF signals, thusfunctioning like an optical waveguide at millimeter-wave frequencies.

Extending this concept further, it was realized that server racks couldbe “pre-wired” such that when a server chassis was installed in a rackslot it could be automatically connected to components in other rackslots via pre-defined connection point in the rack comprising ends ofplastic “cable” waveguides, also referred to herein as simply plasticwaveguides. Optionally, dielectric “manifolds” may be coupled to orintegrated in the plastic waveguides to further facilitate coupling ofmillimeter-wave RF signals between the EHF transceiver chips and theplastic waveguide connection points.

Various exemplary configurations illustrating transfer ofmillimeter-wave RF signals between pairs of EHF transceiver chips 100and 102 using plastic waveguides are shown in FIGS. 3e-3h . In FIG. 3e ,a pair of EHF transceiver chips 100 and 102 have a similar horizontalconfiguration and a plastic waveguide 300 has an elongated “U”-shape. Inthis example, EFT transceiver chips 100 and 102 are substantially in thesame plane and the “legs” of plastic waveguide 300 are substantiallyequal; however, it will be recognized that EHF transceiver chips havingsimilar orientations may be in different planes, and a plasticwaveguide's legs may have different lengths.

FIG. 3f depicts a configuration under which millimeter-wave RF signalsfor EHF transceiver chips 100 and 102 differ by 90 degrees and arecoupled via an elongated U-shaped plastic waveguide 302 having legs ofdifferent lengths. Similarly, the EHF transceiver chips 100 and 102 inFIG. 3g differ by 90 degrees, and have their millimeter-wave RF signalscoupled via an L-shaped plastic waveguide 304. Another configurationemploying an L-shaped plastic waveguide 306 coupling millimeter-wavesignals between EHF transceiver chips 100 and 102 having the sameorientation but in different planes is shown in FIG. 3 h.

In addition to facilitating communication between pairs of EHFtransceiver chips, plastic waveguide may be configured to facilitatecommunication between multiple EHF transceiver chips. For example, FIG.3i depicts a configuration under which millimeter-wave RF transmittersignals for three EHF transceiver chips 100, 102, and 104 are couple viaa plastic waveguide 308 with three legs. More generally, this scheme maybe extended to facilitate communication between n EHF transceiver chipsusing plastic waveguides with n legs. As before, the length of the legsmay be the same or may differ.

Generally, the legs or other receiving members of a plastic waveguidemay either extend into a chassis in which an EHF transceiver chip isdisposed, or the millimeter-wave RF signals may pass through holes in achassis baseplate, top-plate, or walls in a manner similar to shown inFIGS. 4a-4f, 5a-5f , 6 and 7. For instance, FIG. 3i-a shows aconfiguration under which millimeter-wave RF signals transmitted fromand received by EHF transceiver chips 100, 102, and 104, pass throughholes 310 in a sheet metal plate 312 and are coupled to the ends of legs314, 316, and 318 of plastic waveguide 308. Meanwhile, FIG. 3i-billustrates a configuration under which legs 314, 316, and 318 ofplastic waveguide 308 extend through holes 310 in sheet metal plate 312.

FIGS. 17a-17g show various levels of details of an embodiment employinga pair of rack level pre-installed interconnects 1700 a and 1700 b. Asshown in FIGS. 17a and 17b , pre-installed interconnects 1700 a and 1700b include a plurality of plastic waveguides 1702 having a top portionincluding a plurality of legs 1704 and a vertical portion that extendsdown the sides of a rack 1706 having a pair of “top of rack” switches1708 and 1710 (also shown as “Switch A” and “Switch B,” respectively),and having a plurality of slots in which respective server chassis 1712are installed. In the illustrated embodiment, the plastic waveguides areconfigured spaced at substantially fixed spacing that is maintained by aplurality of guides 1714. In one embodiment, guides 1714 are mounted tothe sides of the rack (which are not shown so as not obscure detailsthat would otherwise be hidden). In one embodiment, pre-installedinterconnect 1700 a and 1700 b may be assembled as shown in FIG. 17bprior to installation to the rack. Optionally, guides 1714 may first bemounted to the rack, and then plastic waveguides 1702 may be installedin slots in guides 1714.

FIGS. 17c-17e show further details of server chassis 1712, according toone embodiment. A plurality of holes 1716 are formed in side plates 1718and 1720 of each server chassis 1712, wherein the pattern of the holesare configured to be proximate to respective plastic waveguides when theserver chassis is installed in the rack. Meanwhile, an EHF transceiverchip is located proximate to one or more of holes 1716. Generally, anEHF transceiver chip may be mounted to a vertical board that is orientedparallel to side plates 1718 and 1720, or perpendicular to the sideplates. This latter configuration is shown in the embodiment of FIG. 17d, wherein each of multiple microserver boards 1722 include an EHFtransceiver chip 1724 that is located toward the edge of the boardproximate to a respective hole 1716. This configuration enables serverchassis to be installed and/or replaced without requiring any wiring tothe server chassis.

As shown in FIGS. 17e and 17f , rack level pre-installed interconnectsmay be used to facilitate communication between components in multipleracks. FIG. 17e depicts four racks 1706 a, 1706 b, 1706 c and 1706 d,each with a pair of top of the rack switches 1708 and 1710. As shown inFIG. 17f , a portion of plastic waveguides 1726 that are communicativelycoupled with server chassis 1712 along the right side of rack 1706 c arerouted to the top plate of top of rack switch 1710 d of rack 1706 d.Similarly, a portion of plastic waveguides 1728 that are communicativelycoupled with server chassis 1712 along the left side of rack 1706 d arerouted to the top plate of top of rack switch 1710 c of rack 1706 c.Switching functionality provided by each of top of the rack switches1708 and 1710 facilitate coupling of signals between server chassis 1712in racks 1706 c and 1706 d. This scheme is similarly extended tofacilitate communication between server chassis in each of racks 1706 a,1706 b, 1706 c, and 1706 d.

FIGS. 18a and 18b show further details of a top of the rack switch 1708or 1710, according to one embodiment. The top of the rack switchincludes a circuit board 1800 in which a plurality of EHF transceiverchips 1802 are installed, each disposed opposite a respective hole 1804formed in a top plate 1806 or a chassis 1808. A plurality of networkconnectors 1810 are mounted to the rear side of circuit board 1800, withvarious wire traces and via connecting the EHF transceiver chips tonetworks switch circuitry, as illustrated by a network switch chip 1812.Generally, the location of the EHF transceiver chips and holes willcorrespond to the location of legs 1704 the plastic cable waveguides ofpre-installed interconnects 1700 a and 1700 b. Depending on theimplementation, the end of legs 1704 may or may not extend through theholes 1804.

Another embodiment of a rack level pre-installed interconnect scheme isshown in FIGS. 19a-19e . As shown in FIG. 19a , a plurality of serverchassis 1900 are installed in respective slots in a rack 1902, with setsof plastic waveguides 1904 and 1906 extending up and down the left andright sides of rack 1902. As shown in FIG. 19b , plastic waveguides 1906are configured in an overlapping configuration under which there are atotal of 32 plastic waveguides at the top of each side of the rack.

FIG. 19c shows details of one embodiment of server chassis 1900, whichincludes four server modules each including a processor 1910, aplurality of memory modules 1912, and a network interface controllercard (NIC) 1914. As further detailed in FIGS. 19d and 19e , each NIC1914 includes a plurality of EHF transceiver chips 1916, 1918, 1920, and1922. Each of these EHF transceiver chips is disposed proximate to arespective dielectric manifold 1924, 1926, 1928, and 1930, which in turnare respectively coupled to a plastic waveguide 1932, 1934, 1936, and1938. As further shown, these plastic waveguides are generally flat inshape and are configured in a stacked manner. For convenience, the sideplate of server chassis 1900 is not shown, and the side panel 1940 ofrack 1902 is shown as being transparent. In an actual implementation,both of the server chassis side plates and the rack side panels wouldinclude holes having a pattern that matches the configuration of the EHFtransceiver chips and dielectric manifolds.

Generally, dielectric manifolds such as illustrated in FIGS. 19d and 19emay be used to facilitate coupling of millimeter-wave RF signals to andfrom plastic waveguides. The particular materials and configuration ofthe dielectric manifolds may generally depend on the particular RFfrequency employed by the EHF transceiver chips. The plastic waveguidesthemselves have dielectric characteristics relative to themillimeter-wave RF signals, and thus in some embodiments the dielectricmanifolds may be integrally formed with the plastic waveguides using asingle plastic material. In other embodiments, the dielectric manifoldsmay be made of a different material than the plastic waveguide material.

In general, the plastic multiple waveguides may be configured in avariety of different cross-sections ranging from substantially flat toround. Additionally, the cross-section may also vary along its length.Also, multiple plastic waveguides may be combined in a bundle along aportion of their length, such as exemplified by the stackedconfiguration illustrated in FIGS. 19a-19e , as well as other bundledconfigurations. Preferably, areas of the waveguides that would be incontact in the bundle are separated by a conductive film or sheet, orotherwise means are provided for preventing millimeter-wave RF signalsfrom being coupled between plastic waveguides.

Embodiments implementing the principles and teachings here provideseveral advantages over conventional approach. First, by facilitatingmillimeter-wave wireless links between EHF transceiver chips disposed inseparate chassis, components that are directly or indirectlycommutatively coupled to EHF transceiver chips are enabled to pass datato and receive data from components in other chassis without using awire or optical cable connected between the chassis. This results in acost savings, and also prevents wiring errors such as might result whenconnecting a large number of cables between chassis in a rack. Since theEHF transceiver chips are mounted to backplanes and other circuitboards, their implementation can be mass produced at a relatively lowmarginal cost (compared to similar components without the chips).Additionally, since no cable connections are required chassis can beeasily removed for racks for maintenance such as replacement or upgradeof server blades or modules without having to disconnect and thenreconnect the cables or otherwise need to employ extra cable lengths toallow for maintenance of chassis components.

In addition to using separate types of EHF communication techniques(e.g., EHF transceiver chip-to-EHF transceiver chip, orchip-to-waveguide-to chip) for a given chassis, the two techniques maybe combined for coupling signals to and from the chassis. For example, atop of rack switch could couple signals to another top of rack switch inanother rack using plastic cable waveguides, while coupling signals to achassis below it using chip-to-chip signal coupling.

The following examples pertain to further embodiments. In an embodiment,a method is implemented that facilitates transfer of data betweencomponents in separate chassis using EHF transceiver chips and plasticcable waveguides. In accordance with the method, EHF transceiver chipsare operatively coupled to first and second components in respect firstand second chassis. A plastic cable waveguide is coupled to at least oneof the first or second chassis, or a rack in which the first and secondchassis are installed. The plastic cable waveguide includes first andsecond respective millimeter-wave RF coupling means located proximate toeach of the first and second EHF transceiver chips. Communicationbetween the first and second components is facilitated by transmitting amillimeter-wave RF signal from the first EHF transceiver chip to thesecond EHF transceiver chip via the plastic cable waveguide. Moreover,bi-direction communication between the components is supported by alsotransmitting millimeter-wave RF signals from the second EHF transceiverchip to the first EHF transceiver chip via the plastic cable waveguide.

In an embodiment of the method, the first and second chassis areinstalled in the same rack. In another embodiment of the method, thefirst and second chassis area installed in separate racks. Inembodiments of the method the EHF transceiver chips use a 60 GHz carrierfrequency and support a transfer bandwidth of up to 6 gigabits persecond.

In an embodiment of the method, the millimeter-wave RF signal istransmitted via the plastic cable waveguide by transmitting amillimeter-wave RF signal from an antenna of the first EHF transceiverchip toward a first end of the plastic cable waveguide, which comprisesa millimeter-wave radio frequency (RF) coupling means and is configuredto couple the millimeter-wave RF signal into the plastic cablewaveguide. In an embodiment, at least one of the first and secondmillimeter-wave RF coupling means comprises a dielectric manifold thatis coupled to the plastic cable waveguide.

In another embodiment of the method the plastic cable waveguide includesa plurality of legs along a portion of its length, each comprising arespective millimeter-wave RF coupling means. A respective EHFtransceiver chip is disposed proximate to each of the plurality of legs,and millimeter-wave RF signals are coupled into each of the plurality oflegs transmitted from the respective EHF transceiver chip disposedproximate to that leg. Similarly, millimeter-wave RF signals are coupledout of each of the plurality of legs toward the respective EHFtransceiver chip disposed proximate to that leg.

In accordance with further embodiments, apparatus are configured withmeans for performing the foregoing method operations. In an embodimentof an apparatus, the apparatus comprises a first chassis including afirst component having a first EHF transceiver chip operatively coupledin communication therewith, and a second chassis including a secondcomponent having a second EHF transceiver chip operatively coupled incommunication therewith. A first plastic waveguide is operativelycoupled to at least one of the first and second chassis, having a firstend proximate to the first EHF transceiver chip and a second endproximate to the second EHF transceiver chip. The first plasticwaveguide is configured to facilitate a bi-directional millimeter-wavecommunication link between the first and second EFH transceiver chipswhen the first and second components are operating.

In an embodiment of the apparatus, the first EHF transceiver chip islocated within a chassis frame of the first chassis, and the chassisframe includes a hole proximate to the first EHF transceiver chip thatis configured to enable millimeter-wave RF signals transmitted from andreceived by the first EHF transceiver chip to be passed through thehole. In one embodiment the first component comprises a networkinterface component or network adaptor. In another embodiment, the firstcomponent comprises a server blade or server module to which the firstEHF transceiver chip is coupled. In yet another embodiment, the firstcomponent comprises a backplane to which the first EHF transceiver chipis mounted. In embodiments of the method the EHF transceiver chips use a60 GHz carrier frequency and support a transfer bandwidth of up to 6gigabits per second.

In an embodiment of another apparatus, a chassis frame includes a metaltop plate in which a plurality of holes are formed, and a backplane,mounted to the chassis frame proximate to the metal top plate, having aplurality of EHF transceiver chips mounted thereto, wherein theplurality of EHF transceiver chips are aligned with the plurality ofholes formed in the metal top plate. The apparatus further includes atleast one plastic waveguide having a plurality of legs, each legdisposed proximate to a respective EHF transceiver chip. The componentsare configured such that upon operation of the apparatus,millimeter-wave RF signals transmitted from each EHF transceiver chip iscoupled into the plastic waveguide via the leg that is disposedproximate to the EHF transceiver chip.

In one embodiment, the backplane further comprises switching circuitrythat is communicatively coupled to the plurality of EHF transceiverchips and a plurality of network connectors commutatively coupled to theswitching circuitry. In one exemplary use of this embodiment, theapparatus is implemented as a top of the rack switch. In an embodiment,at least one of the plurality of the legs extends through a respectivehole in the metal top plate. In an embodiment, the plurality of EHFtransceiver chips are configured in a plurality of rows, and theapparatus further comprises a respective plastic waveguide having aplurality of legs for each row, wherein each leg of the respectiveplastic waveguide is disposed proximate to a respective EHF transceiverchip in the row.

In another embodiment of an apparatus, a plurality of plastic cablewaveguides are coupled to a plurality of guides, and each of the guidesconfigured to be mounted to at least one of a server rack or a membercoupled to the server rack. Each plastic cable waveguide are configuredfor coupling millimeter-wave RF signals between the plastic cablewaveguide and an EHF transceiver chip.

In an embodiment of the apparatus, the millimeter-wave RF signals employa 60 GHz carrier frequency. In an embodiment of the apparatus, the EHFtransceiver chips and plastic cable waveguides are configured to supportcommunication bandwidths of up to 6 gigabits per second. In an aspect ofsome embodiment, multiple plastic cable waveguides are bundled togetheralong a portion of their length. In one embodiment, the plastic cablewaveguides are bundled in a stacked configuration.

In an embodiment, the apparatus further includes a server rack to whichthe plurality of guides are operatively coupled and having a pluralityof server chassis slots configured to receive respective server chassis,where at least one server chassis slot includes at least one aperturethrough which millimeter-wave RF signals are enabled to pass. Theinstallation is configured such that when a server chassis including aplurality of EHF transceiver chips is installed in a server chassis slotincluding at least one aperture a respective means for couplingmillimeter-wave RF signals is disposed proximate to a respective EHFtransceiver chip included with the server chassis. In accordance with anaspect of this embodiment, at least a portion of the means for couplingthe millimeter-wave RF signals are configured in a pattern and the atleast one aperture comprises a plurality of holes in a side panel of theserver rack having a pattern that matches the pattern.

In accordance with another aspect of the apparatus, at least one of theplurality of plastic cable waveguides is configured to couplemillimeter-wave RF signals between a first EHF transceiver chip disposedin the server rack to a second EFH transceiver chip disposed in anotherserver rack. In an embodiment of the apparatus, at least one of theplurality of plastic cable waveguide includes a plurality of legs,wherein each leg is configured for coupling millimeter-wave RF signalsinto and out of that plastic cable waveguide. In an embodiment,dielectric manifolds are coupled to at least one plastic cable waveguideor integrally formed with at least one plastic cable waveguide.

In an embodiment of another method, a plurality of plastic cablewaveguides are coupled to a server rack having a plurality of slotsconfigured to receive a respective server chassis, at least a portion ofthe server chassis including at least one EHF transceiver chip, whereinwhen the at least a portion of the server chassis are installed in theserver rack the plastic cable waveguides are configured to couplemillimeter-wave RF signals between transceiver chips in the serverchassis. In an embodiment, the plurality of plastic cable waveguides arepre-installed, and at least one server chassis is enabled to beinstalled and removed from a corresponding slot in the server rackwithout requiring physical connection or disconnection of any wire oroptical cables. In an exemplary implementation, the plastic cable guidesare configured to communicatively couple signals from server chassis ina rack to a top of the rack switch in the rack.

In an embodiment, the method further includes operatively coupling asecond plurality of plastic cable waveguides to at least one of twoadjacent server racks, at least one of the racks including serverchassis and a switch chassis including a plurality of EHF transceiverchips, wherein the second plurality of waveguides are configured tocouple millimeter-wave RF signals between transceiver chips in at leastone of server chassis and switch chassis in separate racks. In anexemplary implementation each of the adjacent server racks includes atop of the rack switch including a plurality of EHF transceiver chips.In accordance with an embodiment of this implementation, a firstplurality of plastic cable waveguides are employed to communicativelycouple signals from server chassis in a first rack to a top of the rackswitch in the first rack, while a second plurality of plastic cablewaveguides are employed to communicatively couple signals between thetop of the rack switch in the first rack to the top of the rack switchin the adjacent rack.

Although some embodiments have been described in reference to particularimplementations, other implementations are possible according to someembodiments. Additionally, the arrangement and/or order of elements orother features illustrated in the drawings and/or described herein neednot be arranged in the particular way illustrated and described. Manyother arrangements are possible according to some embodiments.

In each system shown in a figure, the elements in some cases may eachhave a same reference number or a different reference number to suggestthat the elements represented could be different and/or similar.However, an element may be flexible enough to have differentimplementations and work with some or all of the systems shown ordescribed herein. The various elements shown in the figures may be thesame or different. Which one is referred to as a first element and whichis called a second element is arbitrary.

In the description and claims, the terms “coupled” and “connected,”along with their derivatives, may be used. It should be understood thatthese terms are not intended as synonyms for each other. Rather, inparticular embodiments, “connected” may be used to indicate that two ormore elements are in direct physical or electrical contact with eachother. “Coupled” may mean that two or more elements are in directphysical or electrical contact. However, “coupled” may also mean thattwo or more elements are not in direct contact with each other, but yetstill co-operate or interact with each other.

An embodiment is an implementation or example of the inventions.Reference in the specification to “an embodiment,” “one embodiment,”“some embodiments,” or “other embodiments” means that a particularfeature, structure, or characteristic described in connection with theembodiments is included in at least some embodiments, but notnecessarily all embodiments, of the inventions. The various appearances“an embodiment,” “one embodiment,” or “some embodiments” are notnecessarily all referring to the same embodiments.

Not all components, features, structures, characteristics, etc.described and illustrated herein need be included in a particularembodiment or embodiments. If the specification states a component,feature, structure, or characteristic “may”, “might”, “can” or “could”be included, for example, that particular component, feature, structure,or characteristic is not required to be included. If the specificationor claim refers to “a” or “an” element, that does not mean there is onlyone of the element. If the specification or claims refer to “anadditional” element, that does not preclude there being more than one ofthe additional element.

As used herein, a list of items joined by the term “at least one of” canmean any combination of the listed terms. For example, the phrase “atleast one of A, B or C” can mean A; B; C; A and B; A and C; B and C; orA, B and C.

As discussed above, various aspects of the embodiments herein may befacilitated by corresponding software and/or firmware components andapplications, such as software running on a server or firmware executedby an embedded processor on a network element. Thus, embodiments of thisinvention may be used as or to support a software program, softwaremodules, firmware, and/or distributed software executed upon some formof processing core (such as the CPU of a computer, one or more cores ofa multi-core processor), a virtual machine running on a processor orcore or otherwise implemented or realized upon or within amachine-readable medium. A machine-readable medium includes anymechanism for storing or transmitting information in a form readable bya machine (e.g., a computer). For example, a machine-readable medium mayinclude a read only memory (ROM); a random access memory (RAM); amagnetic disk storage media; an optical storage media; and a flashmemory device, etc.

The above description of illustrated embodiments of the invention,including what is described in the Abstract, is not intended to beexhaustive or to limit the invention to the precise forms disclosed.While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the invention, as thoseskilled in the relevant art will recognize.

These modifications can be made to the invention in light of the abovedetailed description. The terms used in the following claims should notbe construed to limit the invention to the specific embodimentsdisclosed in the specification and the drawings. Rather, the scope ofthe invention is to be determined entirely by the following claims,which are to be construed in accordance with established doctrines ofclaim interpretation.

What is claimed is:
 1. A method, comprising: installing a firstremovable chassis in a first slot in a first rack, the first removablechassis having a first component disposed therein to which a firstextremely high frequency (EHF) transceiver chip is electrically coupled;installing a second removable chassis in a second slot in one of thefirst rack and a second rack, the second removable chassis having asecond component disposed therein to which a second EHF transceiver chipis electrically coupled; coupling a plastic cable waveguide to the firstrack if the first and second removable chassis are installed in thefirst rack or to at least one of the first rack and the second rack ifthe first and second removable chassis are respectively installed in thefirst rack and the second rack, the plastic cable waveguide configuredto couple millimeter-wave radio frequency (RF) signals outputted fromthe first EHF transceiver chip into the plastic cable waveguide and tocommunicatively couple the millimeter-wave RF signals to the second EHFtransceiver chip; and facilitating communication between the first andsecond components by transmitting the millimeter-wave RF signals fromthe first EHF transceiver chip to the second EHF transceiver chip viathe plastic cable waveguide, wherein when the first removable chassis isinstalled in the first slot, the plastic cable waveguide is notmechanically coupled to either the first chassis or any component withinthe first chassis.
 2. The method of claim 1, wherein the first andsecond chassis are installed in the first rack.
 3. The method of claim1, wherein the first and second chassis are respectively installed inthe first rack and the second rack.
 4. The method of claim 1, whereinthe first and second EHF transceiver chips use a 60 GHz carrierfrequency.
 5. The method of claim 1, wherein the communication betweenthe first and second components has a bandwidth of 6 gigabits persecond.
 6. The method of claim 1, wherein the millimeter-wave RF signalsare transmitted via the plastic cable waveguide by transmittingmillimeter-wave RF signals from an antenna of the first EHF transceiverchip toward a first end of the plastic cable waveguide, wherein thefirst end is configured to couple the millimeter-wave RF signals intothe plastic cable waveguide.
 7. The method of claim 1, wherein theplastic cable waveguide includes a dielectric manifold that isconfigured to couple the millimeter-wave RF signals between the plasticcable waveguide and one of the first and second EHF transceiver chips.8. The method of claim 1, further comprising facilitating abi-directional communication link between the first and second EHFtransceiver chips via the plastic cable waveguide.
 9. The method ofclaim 1, wherein the second component includes a third EHF transceiverchip electrically coupled thereto, and wherein the plastic cablewaveguide includes at least a first, second, and third leg along aportion of a length thereof, the first, second and third legsrespectively disposed proximate to the first, second, and third EHFtransceiver chips, the method further comprising: coupling themillimeter-wave RF signals outputted from the first EHF transceiver chipinto each of the second and third EHF transceiver chips; and couplingmillimeter-wave RF signals outputted by each of the second and third EHFtransceiver chips into the first EHF transceiver chip.
 10. An apparatuscomprising: a first chassis, configured to be installed in a first slotin a rack, including a first component contained therein having a firstextremely high frequency (EHF) transceiver chip electrically coupledthereto; a second chassis, configured to be installed in a second slotin the rack, including a second component contained therein having asecond EHF transceiver chip electrically coupled thereto; and a firstplastic waveguide, operatively coupled to at least one of the firstchassis, the second chassis, and the rack, having a first end proximateto the first EHF transceiver chip and a second end proximate to thesecond EHF transceiver chip, wherein the first plastic waveguide isconfigured to facilitate a bi-directional millimeter-wave communicationlink between the first and second EFH transceiver chips when the firstand second components are operating, and wherein the first plasticwaveguide is not mechanically coupled to any of the first component, thesecond component, the first EHF transceiver chip and the second EHFtransceiver chip.
 11. The apparatus of claim 10, further wherein thefirst EHF transceiver chip is located within a chassis frame of thefirst chassis, and the chassis frame includes a hole proximate to thefirst EHF transceiver chip that is configured to enable millimeter-waveRF signals transmitted from and received by the first EHF transceiverchip to be passed through the hole.
 12. The apparatus of claim 10,wherein the first component comprises a network interface component ornetwork adaptor.
 13. The apparatus of claim 10, wherein the firstcomponent comprises a server blade or server module to which the firstEHF transceiver chip is electrically coupled.
 14. The apparatus of claim10, wherein the first component comprises a backplane to which the firstEHF transceiver chip is mounted.
 15. The apparatus of claim 10, whereinthe first and second EHF transceiver chips use a 60 GHz carrierfrequency.
 16. An apparatus, comprising: a chassis frame including ametal top plate in which a plurality of holes are formed; a backplane,mounted to the chassis frame proximate to the metal top plate, having aplurality of extremely high frequency (EHF) transceiver chips mountedthereto, wherein the plurality of EHF transceiver chips are aligned withthe plurality of holes formed in the metal top plate; and at least oneplastic waveguide having a plurality of legs, each leg disposedproximate to a respective EHF transceiver chip, wherein upon operationof the apparatus, millimeter-wave radio frequency (RF) signalstransmitted from each EHF transceiver chip is coupled into the at leastone plastic waveguide via the leg that is disposed proximate to the EHFtransceiver chip.
 17. The apparatus of claim 16, wherein the backplanefurther comprises switching circuitry that is communicatively coupled tothe plurality of EHF transceiver chips and a plurality of networkconnectors commutatively coupled to the switching circuitry.
 18. Theapparatus of claim 16, wherein at least one of the plurality of the legsextends through a respective hole in the metal top plate.
 19. Theapparatus of claim 16, wherein the plurality of EHF transceiver chipsare configured in a plurality of rows, and the apparatus furthercomprises a respective plastic waveguide having a plurality of legs foreach row, wherein each leg of the respective plastic waveguide isdisposed proximate to a respective EHF transceiver chip in the row. 20.An apparatus comprising: a rack, having a plurality of chassis slotsconfigured to have removable chassis installed therein, including firstand second chassis slots; a plurality of pre-installed plasticwaveguides, coupled to the rack, having a first set of means forcoupling millimeter-wave radio frequency (RF) signals arranged in afirst pattern, and a second set of means for coupling millimeter-wave RFsignals arranged in a second pattern, wherein the first set of means forcoupling millimeter-wave RF signals are arranged such that when a firstchassis having a first set of extremely high frequency (EHF) transceiverchips arranged in the first pattern is installed in the first chassisslot, a means for coupling millimeter-wave RF signals in the first setof means for coupling millimeter-wave RF signals is disposed proximateto a respective EHF transceiver chip in the first set of EHF transceiverchips; wherein the second set of means for coupling millimeter-wave RFsignals are arranged such that when a second chassis having a second setof extremely high frequency (EHF) transceiver chips arranged in thesecond pattern is installed in the second chassis slot, a means forcoupling millimeter-wave RF signals in the second set of means forcoupling millimeter-wave RF signals is disposed proximate to arespective EHF transceiver chip in the second set of EHF transceiverchips; and wherein the plurality of pre-installed plastic waveguides areconfigured to facilitate a bi-directional millimeter-wave communicationlinks between EHF transceiver chips in the first set of EHF transceiverchips and EHF transceiver chips in the second set of EHF transceiverchips when the first and second set of EHF transceiver chips areoperating.
 21. The apparatus of claim 20, wherein at least a portion ofthe first set of means for coupling millimeter-wave RF signals of theplurality of pre-installed plastic cable waveguides comprise dielectricmanifolds that are configured to couple the millimeter-wave RF signalstransmitted from and received by respective EHF transceiver chips in thefirst set of EHF transceiver chips that are proximate to respectivedielectric manifolds.